Notwithstanding its cultural and touristic significance, Dobrogea offers plenty of “study material” for other sciences as well, such as geology, speleology, geography, history and so on. The lands of Dobrogea are rich in historical sites, tourist resorts, extremely old rock formations and spectacular caves. One of the more recent discoveries occurred in 2011, when workers on a railway project had to blow up a limy hill. After the explosion, the resulting crater revealed the shimmer of water. Dozens of dump trucks filled with stone were used to try and cover up the hole, but to no avail – the crater seemed to swallow up any amount of rubble. Next, the engineers tried to divert the route, but another explosion opened up a new water-filled cave. An ever greater detour was made but, after a while, the railroad’s embankment began to sink. Not long after, the caverns were explored by speleologists, who discovered an impressive cave, featuring stalagmites and various other geological formations, with a pretty complex topography.
Nevertheless, local legends speak of a true subterranean river, which flows in an opposite direction compared to normal rivers, from the valley towards the hills, and with a flow that could easily surpass the Danube. If, today, you visit Constanța County and you ask about an “underground river”, you will surely find those that know about such a thing. And people have seen water bursting from the ground every time the earth was drilled. It is even more peculiar to see such phenomena in a county as dry and lacking in fresh water reserves as Constanța.
Scientists believe that the flow of such an underground river is more likely closer to that of Olt River. To the north of Constanța, at Palazu Mare, there is a high quality iron ore deposit, at a depth of 500 to 1000 meters. Legend has it that this deposit was discovered by sailors whose compasses were disturbed when they sailed near the shore. After the first prospective drillings, the quality of the ore was confirmed and plans were made to begin extraction. The mining operation failed because above the deposit there are layers of limestone filled with cavities through which water circulates. Therefore, this was the first time when the existence of an “Olt”-sized river was established. The iron ore could not be extracted because the mining galleries would be flooded with water; this was also an opportunity to measure the flow of this underground water.
The aquifer is a complex made up of permeable rocks and water. Where does this water come from? In Dobrogea, there are four sources of underground water – water coming from the Prebalcanic Plateau, located in Bulgaria (this is the main source), water coming from the Danube, in the Ostrov-Cernavoda area, and also rainwater and irrigations.
“The source extends for at least 200 square kilometers under Bulgaria and 80 square kilometers under Romania, at a depth of several hundred meters”, says Camelia Dumitrache, Manager of Water Resources for DADL Constanța.
A significant portion of this flow of underground water drains into the Black Sea, directly beneath sea level, and is thus impossible to see. According to specialists, the exact volume of water of this subterranean river cannot be precisely determined, and the only way of monitoring it is by calculating it on the basis of flows measured during drillings. The input of underground water from Bulgaria is nevertheless demonstrated through clear evidence. Thus, in the heart of Dobrogea, the flow of water is around one liter per second, whereas in the “flooded” south, the measured values reach tens of liters per second.
“The aquifer beneath Constanța County drains through two natural drains in the Siutghiol Lake and Mangalia Pond. In terms of volume contained, this is the most important aquifer in Romania”, tells us Adrian Chera, who works for the Dobrogea-Littoral Water management Agency.
It is paradoxical that farmers face droughts every year, yet they sit upon a subterranean lake. “In 2012, there were few chances for us to use irrigations, because of the high cost of water. Unfortunately, the existing adduction canals are severely degraded nowadays. The solution brought forward by farmers was to combat the phenomenon of desertification by filling the irrigation canals with water, in an environmental program that will result in an solution which is both eco-friendly and advantageous for farmers and rural communities” adds Constantin Iancu, president of the League of Farmers’ Associations local branch. Experts say that the underground water volume can remain constant if this reserve is used exclusively to provide the population with potable water.
“Extreme temperatures and droughts have not reduced the volume of water and we do not believe such a reduction will occur in the following years. The amount of water currently extracted from the aquifer can be doubled without significantly affecting the volume of water” affirms Călin Costache, an environmental specialist.
Carmen-Alina Gherghina- claims, in her doctoral thesis presented at the Faculty of Geography of the Bucharest University, that “in the context of a non-existent natural drainage, the influence of irrigations on the hydro-geological processes intensifies, determined by a decrease of underground discharge. There are also a number of additional issues, such as the incorrect use of irrigations, wrong techniques and the losses in the adduction and distribution network, and a poor exploitation”.
“Getting to know these underground waters could lead to better water management in Dobrogea. Because of such resources, the Romanian littoral does not run out of water in summer, when its population triples and consumption is enormous. During this period, water is pumped from the underground deposits” – Cristian Lascu, speleologist and chief editor of national Geographic Romania.
Sources:
http://portal.tfm.ro/legenda-fluviului-subteran-de-sub-dobrogea/
http://www.natgeo.ro/explorari/speologie/9054-misterul-apelor-pierdute-din-dobrogea
http://deltadunarii.fotodelta.ro/?p=2372
Photo source:
http://www.groundwater.org/kc/whatis.html
http://greenly.ro/apa/rezervele-de-apa-din-adancul-dobrogei
Article written by Razvan Spiridon and translated by Mihail Mitoseriu.